Phone for dd

Up to now dd aged 12 has had my old Samsung tocco phone on payg. The tocco has a touch screen but isn't a smart phone.

However, the phone is becoming unreliable (dh had it before me, so it must be over six years old!) so I would like dd to get a new smartphone for her birthday in April.

I know she'd love something expensive, but money won't run to that, so I'm hoping to get her a smartphone on a really cheap contract with enough inclusive mins, texts and data, plus the ability to stop her running up a huge bill.

We are both with O2, but have found them incredibly useless at helping with such things.

Motorola moto g £100 at tesco ( get it unlocked for a few quid) and a cheap sim deal (ovivo is free if you can live within the limits or giffgaff etc)

Cracking phone. No fear of big bills either. The 20yr old got it at Xmas.

Three have some cheap deals in store eg £25 for 2 basic smartphones and they'll cap the contract, but the phones aren't the latest etc - I'm thinking maybe get this and use one at least in my phone, well see...